Detection rules › Kusto

Mimecast Targeted Threat Protection - Impersonation Protect

This is a third-party alert feed, not a detection over modeled telemetry. The vendor product raised the finding; this rule forwards it into the SIEM. It is searchable for reference but is excluded from the detection-rule browse and the ATT&CK coverage matrix.

Severity
high
Time window
15m
Source
github.com/Azure/Azure-Sentinel

Detects a maliciously tagged impersonation

MITRE ATT&CK coverage

TacticTechniques
CollectionT1114 Email Collection

Rule body kusto

id: d8e7eca6-4b59-4069-a31e-a022b2a12ea4
name: Mimecast Targeted Threat Protection - Impersonation Protect
description: Detects a maliciously tagged impersonation
severity: High
requiredDataConnectors:
  - connectorId: MimecastTTPAPI
    dataTypes:
      - MimecastTTPImpersonation_CL
enabled: true
query: MimecastTTPImpersonation_CL| where taggedMalicious_b == true;
queryFrequency: 5m
queryPeriod: 15m
triggerOperator: gt
triggerThreshold: 0
suppressionDuration: 5h
suppressionEnabled: false
tactics:
- Exfiltration
- Collection
- Discovery
relevantTechniques:
- T1114
alertRuleTemplateName:
incidentConfiguration:
  createIncident: true
  groupingConfiguration:
    enabled: true
    reopenClosedIncident: false
    lookbackDuration: 1d
    matchingMethod: AllEntities
eventGroupingSettings:
  aggregationKind: AlertPerResult
entityMappings:
  - entityType: MailMessage
    fieldMappings:
      - identifier: Sender
        columnName: senderAddress_s
      - identifier: SenderIP
        columnName: senderIpAddress_s
      - identifier: Recipient
        columnName: recipientAddress_s
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: source

MimecastTTPImpersonation_CL

Stage 2: where

| where taggedMalicious_b == true;

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
taggedMalicious_beq
  • true transforms: cased